Android:IOException BufferedInputStream在下载后关闭

下载图像后，InputStream出现一些问题。downloadImages方法返回我在文件中写入的InputStream。但是inputStreamToFile方法中有一个异常：java.io.IOException:BufferedInputStream已关闭。代码如下：

下载

public static InputStream downloadImages(String imageUrl) {

        HttpURLConnection httpConn = null;

        String urlBase =  imageUrl;

        if(D) Log.d(TAG, "downloadImages(): url request: " + urlBase);

        try {
            URL url = new URL(urlBase);
            httpConn = (HttpURLConnection) url.openConnection();
            httpConn.setConnectTimeout(SystemConstants.TIMEOUT_CONNECTION);
            httpConn.setReadTimeout(SystemConstants.SOCKET_CONNECTION);

            if (httpConn.getResponseCode() == HttpURLConnection.HTTP_OK) {

                InputStream inputStream = httpConn.getInputStream();
                return inputStream;
            }

        } catch (IOException e) {
            Log.w(TAG, "downloadImages(): exception: " + e);
            e.printStackTrace();
            return null;
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if(httpConn != null) httpConn.disconnect();
        }

        return null;
    }

从IS到文件

public static void inputStreamToFile(InputStream is) {
        if(D) Log.d(TAG, "inputStreamToFile() called");
        OutputStream outputStream = null;

        try {
            // Check if media is mounted or storage is built-in, if so, try and use external cache dir
            // otherwise use internal cache dir

            final String cachePath =
                    Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState()) ||
                            !Utils.isExternalStorageRemovable() ?
                            Utils.getExternalCacheDir(App.getContext()).getPath() :
                            App.getContext().getCacheDir().getPath();
            // write the inputStream to a FileOutputStream
            outputStream = new FileOutputStream(new File(cachePath + File.separator + "vr"));

            int read = 0;
            byte[] bytes = new byte[1024];
                while ((read = is.read(bytes)) != -1) {
                    if(D) Log.d(TAG, "read called");
                    outputStream.write(bytes, 0, read);
                }

        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (is != null) {
                try {
                    is.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (outputStream != null) {
                try {
                    if(D) Log.d(TAG, "inputStreamToFile(): outputStream is not null");
                    outputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }

            }
        }
    }

---

放入日志。然后只有我们才能识别错误、bug等

当您使用第一种方法关闭HttpConnection时，inputstream将被关闭。太好了，非常感谢！但是现在我在哪里关闭连接？！最简单的方法是在下载图像内部调用inputStreamToFile，而不是返回inputStream。另一种解决方案是使用一种方法打开HttpConnection并返回它，另一种方法关闭HttpConnection。然后可以在这两个方法之间访问InputStream。但是错误处理可能有点混乱。